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1.
Carello Giuliana Landa Paolo Tnfani Elena Testi Angela 《Central European Journal of Operations Research》2022,30(1):159-187
Central European Journal of Operations Research - In the past years, the number of patients in need of chemotherapy treatments has been constantly increasing. Chemotherapy treatments must be... 相似文献
2.
Peptidic aminopeptidase inhibitors, bestatin, phebestin and probestin have been prepared by stereo- and regiocontrolled reactions from a common α,β-epoxy ester precursor. 相似文献
3.
Summary We are going to present the focal-mechanism solution of Fruili earthquake occurred on May 6, 1976, as it results from the
analysis, on original seismograms, of the polarities of initial longitudinal waves obtained in 92 seismic stations. The polarities
so obtained have been reported on the projection which represents the surface of the Earth and the solution has been drawn,
directly, from the study of the resulting distribution, by establishing through Gr?fe's theory the two couples of forces considered
as the sources of the seism at the focus. At last, a comparison has been carried out with the solution already obtained by
other authors.
Riassunto Si presenta la soluzione del meccanismo focale del terremoto del Fruili del 6/5/1976 ottenuta dallo studio, sui sismogrammi originali, della polarità delle onde longitudinali iniziali, quale si è presentata in 92 stazioni sismiche vicine e lontane. Le polarità ottenute sono state riportate sulla superficie della Terra e la soluzione è stata ricavata direttamente dallo studio della distribuzione così ottenuta, definendo mediante la teoria di Gr?fe le due coppie di forze che hanno agito all'ipocentro. Un confronto è stato infine eseguito con le soluzioni in precedenza ottenute da altri autori.
Резюме Предлагается решение фокального механизма землетрясения, имевшего место в Фриули 6 мая 1976 г. Решение есть результат анализа исходных сейсмограмм, которые получены на 92 сейсмнческих, удаленнынных и близких. Полученные пояьрности представлены в проекции на поверхность Земли. Решение получено непосредственно из исследования результируюшего распределения, которое следует из теории Грефа для для двух пар сил, представляюших источники землетрясения в фокусе. В заключение проводится сравнение с решением, полученным ранее другими авторами.相似文献
4.
S. F. Biagi M. Bourquin R. M. Brown H. J. Burckhart P. Extermann M. Gailloud C. N. P. Gee W. M. Gibson P. Jacot-Guillarmod J. Perrier K. J. Ragan Ph. Rosselet P. Schirato H. W. Siebert V. J. Smith K. P. Streit J. J. Thresher A. T. Wood C. Yanagisawa 《Zeitschrift fur Physik C Particles and Fields》1987,34(2):175-185
In an experiment at the CERN-SPS charged hyperon beam, we have investigated the inclusive \(\Lambda \bar K^0 \) and \(\Sigma ^0 \bar K^0 \) final states formed in Ξ? Be interactions. In the \(\Lambda \bar K^0 \) channel, we observe a signal at 1826 MeV/c2 which can be identified with the known Ξ(1820) resonance. We determine its mass and width to be:M=1826±4 MeV/c2, Г=12±14 MeV/c2. A moment analysis is consistent with a spin of 3/2 and indicates a negative parity for this spin assignment. Also in the \(\Lambda \bar K^0 \) channel, we observe a 3.6σ signal with the following parameters:M=1963±5 MeV/c2, Г=25±15 MeV/c2. This state, which we call Ξ(1960), is not observed in the \(\Sigma ^0 \bar K^0 \) channel, leading to an upper limit on the ratio of partial widths \(\Sigma \bar K/\Lambda \bar K\) of 2.3 (90% confidence level). A moment analysis of the \(\Lambda \bar K^0 \) final state indicates a spin of 5/2 or greater in the natural spin-parity series 5/2+, 7/2?, etc. 相似文献
5.
The CD curves of a set of condensed γ-butyrolactones have been investigated. A simple correlation between the sign of the Cotton effect (CE) and the configuration of C can be deduced from the resulting data. 相似文献
6.
[reaction: see text] Marine diatoms produce alpha,beta,gamma,delta-unsaturated aldehydes that have detrimental effects on the reproduction of their natural predators. The production of these defensive metabolites is suggested to involve enzymatic oxidation of polyunsaturated fatty acids. In this paper, feeding experiments with labeled precursor provide clear evidence in support of the origin of octadienals 1 and 2 from 6,9,12-hexadecatrienoic acid (5), thus proving the involvement of novel lipoxygenase/lyase activity for the oxidation of C(16) fatty acids. 相似文献
7.
Bianco G Schmitt-Kopplin P Crescenzi A Comes S Kettrup A Cataldi TR 《Analytical and bioanalytical chemistry》2003,375(6):799-804
The glycoalkaloid content of transgenic potatoes was evaluated by an optimised method based on non-aqueous capillary electrophoresis coupled on-line with electrospray ionization-mass spectrometry (NACE-ESI-MS). The potato material consisted of tubers from a conventional cv. Désirée and from three lines of modified plants resistant, intermediate and susceptible to infection by potato virus Y (PVY). The main glycoalkaloids were confirmed to be alpha-solanine and alpha-chaconine with parent ion masses m/z 852 and 868, respectively. In addition, an unknown minor peak at m/z 850.6 was found both in conventional (control) and susceptible line potato tubers. Such a compound exhibited an MS(2) spectrum with fragments ions at 704 and 396 m/z derived by loss of two ions, i.e. m/z 146 and 307, most likely corresponding to a rhamnose unit and a [glucose-(rhamnose)(2)] moiety, respectively. Up to 30-80-fold higher concentrations of total glycoalkaloids were found in the peel compared to flesh samples of all tubers examined. TGA content was nearly doubled in peel samples of resistant compared to control lines, and these levels were lower than the limit recommended for food safety, i.e. 20-60 mg of TGA per 100 g fresh weight. Moreover, it was established that tubers produced by virus-resistant clones are substantially equivalent in glycoalkaloid contents to those produced by conventional potato varieties. 相似文献
8.
The complex (1) has been prepared and its structure determined. Complex1 is the first stable thioether derivative of a metal carbonyl containing only cobalt as metal. It crystallizes in the monoclinic P21/c space group, witha = 13.975( 4 ),b = 11.363( 3 ),c = 14.686(2)A, = 112.25(2)°,V = 2158.5(7)A3.Z = 4. The solution using direct methods and the anisotropic refinement of all nonhydrogen atoms led toR = 0.039,wR = 0.041 for 3296 reflections with F> 4.0(F) Analogous but less stable complexes are formed with 1,6-diphenyl-2,5-dithiahexane and the crown thioether 1,4,7-trithiacyclonane, the latter functioning either as a bidenlate or a tridentate ligand. 相似文献
9.
M.C. Guerra A.M. Barbaro G.L. Biagi M.C. Pietrogrande P.A. Borea A. Andreani G.Cantelli Forti 《Journal of chromatography. A》1985,320(2)
The Rm values and retention times of a series of nitroimidazo[2,1-b]thiazoles were obtained by means of thin-layer and high-performance liquid chromatography, respectively. Extrapolated Rm and log k′ values were correlated in a statistically significant way with π values calculated according to the literature. 相似文献
10.
Giuliana Gervasio Domenica Marabello Andrea Secco 《Journal of organometallic chemistry》2004,689(1):35-42
The reaction of Ru3(CO)12 with but-2-yn-1,4-diol (HOCH2CCCH2OH, BUD) in CH3OH/KOH followed by acidification with HCl leads to four products, one of which has been identified as the title complex (μ-Cl)Ru3(CO)9[μ3-η4-H2CCC(H)CH2]. This is an open cluster containing a bridging Cl atom on the open side and a C4H5 moiety bound to all the metals. The structure of the complex has been determined by X-ray analysis.The thermal reaction of Ru3(CO)12 with BUD has been revisited for a comparison with the results in alkaline solution. The main product is the allylic derivative HRu3(CO)9[HCCHCCHO]. 相似文献